Waveguides are used to channel electromagnetic radiation and transport it from an origin to a destination. Typically, radiation such as visible light enters one part of the waveguide, is transported through the waveguide by reflection from the sides of the waveguide, and exits at another part of the waveguide. In certain applications waveguides must be carefully manufactured to very tight dimensional and angular tolerances so that the information content of the radiation traveling through the waveguide is preserved.